<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>6-css3动画案例一</title>
    <style>
        .box{
            width:200px;
            height: 200px;
            background:red;
            /* animation: second .4s; */
            animation-name: second;
            animation-duration: .4s;
        }
        /* move动画名称 */
        @keyframes move{
            from{
                width:200px; 
            }
            to{
                width: 500px;
            }
        }
        @keyframes second{
            0%{
                width: 200px;
            }
            10%{
                width:300px;
            }
            60%{
                width: 500px;
            }
            100%{
                width: 200px;
            }
        }
    </style>
</head>
<body>
    <div class="box"></div>
</body>
</html>